The storylines heading into Super BowlXLVII have been captivating and gotten us through a two-week NFL lull, but on Sunday we finally put them to rest.

It's still intriguing that Ray Lewis' career will end after 17 seasons, that Jim and John Harbaugh are brothers, and that Michael Oher was once the subject of the movie "The Blind Side." But we've heard thousands of variations on each of the stories over the past 14 days.

Enough is enough, and it's time to finally get to the action on the field. The Baltimore Ravens and San Francisco 49ers had different journeys in the regular season, but their postseason ascents oddly mirror one another. The teams went through (arguably) the NFL's four best quarterbacks to get to Super Bowl Sunday, behind signal-callers who entered the playoffs as massive question marks.

With each of the past three Super Bowl MVPs being men under center, it stands to reason that Joe Flacco and Colin Kaepernick will hold the keys to Sunday's game. For that reason, let's take one final look at Sunday's matchup, highlighting the quarterbacks and a few other underrated x-factors in Super Bowl XLVII.

Can the Ravens Limit Colin Kaepernick?

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Very few can deny the paradigm of the 49ers' season shifted when Jim Harbaugh made the switch from Alex Smith to Kaepernick. The former Nevada star brought an explosiveness to San Francisco's offense that the conservative, check-down heavy scheme run with Smith certainly did not have.

That much has been clear throughout the 49ers' playoff run. Could Smith have led a comeback from 17 points down against the Atlanta Falcons in the NFC Championship Game? Possibly. But he certainly wouldn't have set an NFL record with 182 rushing yards versus the Green Bay Packers a week prior. That performance alone justified the switch to Kaepernick and will go down in history.

Simply put, San Francisco has been markedly better with Kaepernick at quarterback. Per Football Outsiders' DVOA metric, only once (Week 16 vs. Seattle Seahawks) have the 49ers had a negative passing value with Kaepernick as a starter.

During his postseason run, Kaepernick has gotten even better under center. He's averaged an astounding 9.54 yards per attempt while cobbling together the only two QBRs of 90 or higher during the playoffs.

That means something will have to give on Sunday. Though the Ravens were middling through the entire season in the secondary, they defeated Peyton Manning and Tom Brady en route to Super Bowl XLVII, limiting both quarterbacks' success down the field. Here is a look at opposing quarterbacks' yards per attempt against Baltimore this postseason, compared to their regular season averages.

Quarterback

Regular Season YPA

YPA vs. Ravens

Andrew Luck

7.0

5.3

Peyton Manning

8.0

6.7

Tom Brady

7.6

5.9

That's been thanks in large part to the presence of Corey Graham. He's been the Ravens' best cornerback since Lardarius Webb's injury and was given the unenviable task of covering Wes Welker two weeks ago. He did a fine job, but it will be interesting to see how Baltimore uses him on Sunday.

While the Ravens certainly have shown the ability to stop great quarterbacks during the playoffs, Kaepernick's running prowess is an X-factor the Ravens haven't seen much this season. They played two games against "mobile" quarterbacks (Week 2 against Michael Vick, Week 14 against Robert Griffin III) and had middling success.

Both Griffin and Vick had 34 rushing yards, with the latter scoring a touchdown. Neither was all that impressive running the ball, but Vick wasn't taking read-option snaps and Alfred Morris carried the rushing load for Washington.

While it stands to reason that the Ravens will see Kaepernick in the pistol formation throughout Super Bowl XLVII, 49ers offensive coordinator Greg Roman has proved he's a schematic chameleon. After Kaepernick's record-setting performance against Green Bay, the 49ers' signal-caller ran only twice in the NFC Championship Game.

Assuming Roman plans to use Kaepernick's rushing ability on Sunday, Baltimore may have trouble keeping pace.

The Ravens aren't going to be able to play a spy the whole game and still have success in pass defense. Their cornerbacks simply aren't good enough to keep tight coverage against Michael Crabtree and Randy Moss.

That puts the onus on the linebacking corps to get the job done, particularly Ray Lewis. He's been a run-stuffing animal during the playoffs with 44 tackles, and Lewis has long been one of the NFL's best read-and-react linebackers.

Whether he still has the range to cover Kaepernick on the outside remains very much up in the air. The folks at Bovada have a betting line that plays Steve Young's longest run in Super Bowl XXIX (21 yards) versus Kaepernick's on Sunday.

All it will take is one bad read from Lewis to have that hit the over and for Kaepernick's feet to perhaps lead his team to victory.

Will Joe Flacco Be Able to Make Plays Down the Field?

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One of the biggest reasons the Ravens trudged through a 10-6 record was the inconsistencies of their offense, particularly at quarterback. Baltimore ranked 30th in offensive variance during the regular season, per Football Outsiders, and actually had a negative DVOA value in half of their contests.

That mostly falls at the feet of Flacco. His ascent during the postseason will likely make him a very rich man come March, but Flacco's play has varied wildly from week to week, with very little rhyme or reason behind it.

During the regular season, Flacco averaged 8.1 yards per attempt in wins, which would rank second among qualified quarterbacks. In losses, though, Flacco's YPA dipped all the way to 5.5, an NFL-worst rate by about a half-yard.

It's not exactly reinventing the wheel to say quarterbacks perform better in wins than losses. That's an understatement on the level of calling Ray Lewis an "emotional leader."

Flacco's level of variance is the true story. Only Robert Griffin III and Russell Wilson had bigger differences in their yards per attempt averages among playoff quarterbacks.

As one would expect, Flacco has had great success throwing down the field during the playoffs. He's averaged a whopping 9.17 yards per attempt, with the AFC Championship being the only contest where he did not have a completion of 50 yards or more.

How will Flacco fare against San Francisco's secondary? That all depends on whether you want to look at the season-long numbers or recent trends.

According to Football Outsiders, the 49ers had the league's best DVOA on passes thrown 15 or more yards down the field. On paper, that makes them the perfect contrast to Baltimore and the Ravens' throw-deep-first-ask-questions-later offensive attack.

However, recent trends point toward San Francisco's defense being far weaker since Justin Smith's triceps injury. He's played through the pain and has been somewhat effective, but Smith's dominance has become increasingly apparent as the playoffs have gone along.

After allowing 5.24 yards per passing play from Weeks 1-15, opposing offenses have improved by nearly two full yards over San Francisco's past four games, per Football Outsiders. That was especially evident two weeks ago when Atlanta Falcons receiver Julio Jones torched the 49ers, catching 11 passes for 182 yards and two first-half touchdowns.

Facing off against San Francisco's top corner Tarell Brown for most of the contest, Jones was able to continually get open underneath. He made seven of his receptions while being covered by Brown, per Pro Football Focus, including a 20-yard touchdown in the second quarter.

But where Jones really made his hay was in zone coverage reads, where DashonGoldson missed two critical coverages down the field. Targeted only four times by Matt Ryan, Goldson gave up 92 yards on those plays, 73 of which went to Jones on downfield targets.

If Flacco is able to replicate Ryan's success down the field with Torrey Smith or even Anquan Boldin, Baltimore has a very good chance at winning on Sunday. However, if the opposite is true and the 49ers return to regular-season form, we may wind up with a blowout on our hands.

Which X-Factor Will Step Up?

Quarterbacks win championships. NFL fans have had enough talking head features over the past decade to know that's an irrefutable fact, and we've already talked about the guys under center ad nauseum in this space.

What about the guys not involved in the passing game? We've seen non-quarterbacks shift plenty of Super Bowls in the past, and there are a couple guys who could do the same on Sunday.

Here is a look at a couple of the most likely underrated x-factors for Sunday night.

Jacoby Jones (KR/PR, Baltimore Ravens)

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Thanks in large part to Jones and kicker Justin Tucker, the Ravens ended the 2012 regular season with easily the NFL's best special teams. According to Football Outsiders, the Ravens' 9.0 percent DVOA was nearly a full three percent better than the second-best team (Cleveland Browns) and was one of the best units in history.

Though the rookie, Tucker, will certainly play an integral role (as kickers tend to do in Super Bowls), Baltimore will need Jones to come up with at least one massive return Sunday. The return specialist led the NFL with a 30.7 yards per kick return average, accounting for 13.3 points better than league average.

That should come into play against San Francisco.

Kicker David Akers has gone through a miserable campaign kicking the ball through the uprights, but his struggles on kickoffs could play a bigger factor on Sunday. During the regular season, opponents started their drives at the 25.3-yard line when Akers kicked off, which was 26th among players who attempted 50 or more kickoffs.

If Akers is unable to force touchbacks and Jones gets multiple opportunities to return the ball against San Francisco's mediocre coverage team, he may well shift the momentum of the entire game.

Aldon Smith (LB, San Francisco 49ers)

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The 49ers' aforementioned struggles defensively have coincided with Justin Smith's triceps injury, but the disappearing act done by Aldon Smith has been far more disconcerting.

A dominant force for the first 15 weeks of the season, Aldon Smith was seemingly on the precipice of breaking Michael Strahan's sacks record (22.5) prior to Week 15. He was beating the NFL's best tackles off the edges and was competing with J.J. Watt for Defensive Player of the Year honors.

However, Smith's pass rushing ability has gone radio silent in San Francisco's past five games. He hasn't recorded as sack since Dec. 9 against the Miami Dolphins, and has been a noticeable liability on run defense to boot.

With Justin Smith's effectiveness very much in question heading into Sunday, Aldon will have to find himself and fast. The 49ers will need to create pressure on Flacco to avoid any downfield completions, and Aldon Smith is their only elite sacks man.

Baltimore's offensive line should have trouble with Smith's speed. Bryant McKinnie took over the left tackle role in Week 17, and while he's been surprisingly solid, it's hard to see him keeping up with Smith the entire game.

Prediction

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As you may have picked up on, Sunday will be a contest pitting one team that has been excellent for the entire season against one that seemingly peaked at the right moment.

With two weeks off, I favor the team that has been consistently great. Look for Kaepernick to have success in both facets of the game, as the 49ers come away with a relatively sound victory.